I bought a set of the XTR rings when they first came out. As for appearance, they looked good with a nice anodizing that was even and a good matte finish. I mounted them up on my rifle and torqued the 1/2" nut down to 65 inch pounds as is standard with these type rings. I don't recall seeing anything different for torque specs from Burris. My scope fit fine in the rings but when threading the cap screws down, the metal actually felt soft, softer than other aluminum rings I had. Afterword, I removed the rings from the scope base and noticed that the 1/2" nut had scored the clamping foot, left a nice little ring where the nut tightened against it. This confirmed my suspicion that the metal was soft. So this just led to me being skeptical about the overall durability and quality of the material the rings were made with. I never really gave them a chance after that. I used them for a short while until I found other rings I felt were better quality to replace them with.
I still have the XTR's sitting on my shelf. I actually ended up backing the 1/2" nut off and placing a cheap washer between the nut and the clamping foot so that subsequent tightening of the nut wouldn't lead to further scoring of the clamp. But like I said, I haven't really gave them a chance to perform and definately haven't trusted them to hold my scope for any length of time.
These were original rings though, so improvements may have been made. I'm just not going to spend any more money on these particular rings for a serious duty grade rifle. jI stick with the Badger, Seekins, and Vortex which have proven to be of the highest quality. Nightforce rings would be great as well as many other companies' rings.
Geb